Tag: M.W=200-250

Crofts, Peter C. published the artcileThe preparation and the determination of apparent dissociation constants of some substituted aliphatic phosphonic acids, SDS of cas: 66197-72-6, the publication is Journal of the American Chemical Society (1953), 5738-40, database is CAplus.

cf. C.A. 47, 12220f. An examination was made of the effect produced on the dissociation constant of MePO₃H₂ (I) by the substitution of 1, 2, or 3 Cl atoms, 1 Br, or 1 iodine atom, or an HO group in the Me group of I, the simplest phosphonic acid. The acids produce on titration the expected curves with 2 inflection points, but because of the very considerable acid strength of the 2nd H of Cl₃CPO₃H₂ (II) the 1st inflection point cannot be satisfactorily determined by chem. indicators. The substitution of halogens or of a HO group increases the acid strength of I. For the acids studied, pK’_a1 and pK’_a2 are: ClCH₂PO₃H₂ (III), 1.40, 6.30; Cl₂CHPO₃H₂ (IV), 1.14, 5.61; II, 1.63, 4.81; BrCH₂PO₃H₂ (V), 1.14, 6.52; ICH₂PO₃H₂ (VI), 1.30, 6.72; HOCH₂PO₃H₂ (VII), 1.91, 7.15; I, 2.38, 7.74. For most of the following compounds, the methods presented were developed after unsuccessful attempts to prepare the compounds by other methods. Paraformaldehyde (10 g.) and 71 g. PCl₃ heated 11.5 hrs. at 240-50° in a sealed tube yielded 67% ClCH₂POCl₂ (VIII), b_16.5 93°. VIII stirred slowly into excess water and the solution evaporated to dryness in vacuo yielded III, m. 88° after softening at 85°. Hydrolysis of Cl₂CHPOCl₂ (Kinnear and Perren, C.A. 47, 5878h) by the method for III yielded IV, m. 116-19°. P(OEt)₃ (IX) and CCl₄ (Kosolapoff, C.A. 41, 5851i) yielded the di-Et ester of II which was refluxed 6 hrs. with 100 cc. HCl and 50 cc. water, and the resulting solution treated with C and evaporated to give II, m. 85-7°; dried over P₂O₅ at 0.05 mm., it m. 163.5°, after softening at 161°. IX (126 g.) and 162 g. CH₂Br₂ autoclaved 4 hrs. at 172° yielded the di-Et ester of V, which, refluxed 9 hrs. with 48% HBr, gave V, m. 62°, after softening at 54°. IX and CH₂I₂ yielded the di-Et ester (X) of VI, b_0.01 61°, 23.6 g. of which, refluxed 1 day with 100 cc. HCl and 50 cc. water, gave VI, m. 89°, after softening at 86°. X (25 g.) and 40.3 g. AgF slowly heated in a distillation apparatus 5 hrs. at about 30 mm. yielded 2.3 g. distillate, yielding on redistillation the di-Et ester of I, b₂₁ 91-2°. The method of Page (C.A. 6, 2064) gave VII, m. 99-100°.

Journal of the American Chemical Society published new progress about 66197-72-6. 66197-72-6 belongs to bromides-buliding-blocks, auxiliary class Aliphatic Chain, name is Diethyl (bromomethyl)phosphonate, and the molecular formula is C5H12BrO3P, SDS of cas: 66197-72-6.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Al-Zoubi, Raed M. published the artcileMild Silver(I)-Mediated Regioselective Iodination and Bromination of Arylboronic Acids, Product Details of C7H8BBrO3, the publication is Organic Letters (2010), 12(11), 2480-2483, database is CAplus and MEDLINE.

A convenient and regioselective silver(I)-mediated electrophilic iodination and bromination reaction of arylboronic acids has been developed. The boronic acid does not require protection prior to the reaction, which can be performed on a multigram scale with moderate to excellent yields. A mild, simple, and effective method is disclosed to provide ortho-haloarylboronic acids, e.g. I, that can be used as useful intermediates in selective sequential Suzuki-Miyaura cross-coupling reactions to provide ortho-triaryl derivatives, e.g. II, in good yields.

Organic Letters published new progress about 89694-44-0. 89694-44-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is 2-Bromo-5-methoxybenzene boronic acid, and the molecular formula is C7H8BBrO3, Product Details of C7H8BBrO3.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Brueckner, Alexander C. published the artcileVisible-light-mediated, nitrogen-centered radical amination of tertiary alkyl halides under metal-free conditions to form α-tertiary amines, Product Details of C6H12Br2, the publication is Organic & Biomolecular Chemistry (2016), 14(19), 4387-4392, database is CAplus and MEDLINE.

A mild and operationally convenient amino-functionalization of a range of tertiary alkyl halides by reaction with iminoiodinanes (PhI=NNs) and I₂ was developed. According to the mechanistic experiments described within the reaction was speculated to proceed through a light-promoted, N-centered radical pathway involving a N,N-diiodosulfonamide reactive species. This method of direct N-incorporation offers an attractive alternative to the production of α-tertiary amines, a synthetically challenging structural class found in a variety of bioactive mols.

Organic & Biomolecular Chemistry published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Product Details of C6H12Br2.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kofron, William G. published the artcileDisplacement on halogen vs. carbon and on halogen vs. hydrogen of certain polyhalides by diphenylmethide ion in liquid ammonia, Name: 2,3-Dibromo-2,3-dimethylbutane, the publication is Journal of the American Chemical Society (1968), 90(15), 4126-9, database is CAplus.

Na and K diphenylmethide (I), prepared from diphenylmethane (II) and the corresponding alkali amide in liquid NH3 underwent displacement on halogen with ethylene bromide and iodide to form the dimer, 1,1,2,2-tetraphenylethane (III), and presumably ethylene; in contrast, I underwent displacement on C (SN2) with ethylene chloride to give the twofold alkylation product. Similarly, potassio salt I underwent displacement on halogen with 2,3-dibromo-2,3-dimethylbutane, 1,1,2,2-tetrabromoethane, and hexachloroethane to form dimer III and an olefinic product. The olefinic products from the tetrabromo- and hexachloroethanes were dibromoethylene and tetrachloroethylene, resp., potassio salt I also underwent displacement on halogen with these olefinic halides to afford apparently acetylene. Potassio salt I underwent diplacement on H with 1,1-dichloroethane to regenerate II, and displacement on halogen with 1,1,1-trichloroethane and benzotrichloride to form a mixture of II and III; in these cases the halide was converted to an alddimine. Potassio salt I underwent displacement on halogen with N-bromosuccinimide to give dimer III and succinimide.

Journal of the American Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Name: 2,3-Dibromo-2,3-dimethylbutane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Crimmins, Michael T. published the artcileIntramolecular photocycloaddition-cyclobutane fragmentation: total synthesis of (±)-laurenene, Formula: C7H13BrSi, the publication is Journal of the American Chemical Society (1987), 109(20), 6199-200, database is CAplus.

Nature’s only known existing fenestrane, laurenene (I) was prepared via an elevated temperature intramol. [2+2] photochem. cycloaddition of diene II. This established the highly sterically congested center of the laurenene skeleton which contains 3 contiguous quaternary C. Reductive cleavage of the cyclobutane produced during the photocycloaddition provides an intermediate which was used to form the remaining 7 membered ring via an intramol. aldol-dehydration reaction. The [5.5.5.7] fenestrane III which was prepared in 12.7% yield was transformed to I in 5 steps.

Journal of the American Chemical Society published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Formula: C7H13BrSi.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Casalta, Clement published the artcileIridium(III) Catalyzed Z-Selective Allylic Arylation of α-Fluoro But-1-enoic Acid Amides via β-F-Elimination in Water, Synthetic Route of 89694-44-0, the publication is Organic Letters (2021), 23(21), 8122-8126, database is CAplus and MEDLINE.

Allylic arylation of α-fluoro but-1-enoic acid amides with arylboronic acids was carried out in water by comparing the catalytic activity of iridium(III) and rhodium(III). Ir(III) has shown a strong superiority over Rh(III) to give allyl-aryl coupling products with excellent stereoselectivity in favor of the Z-isomer. The origin of high stereoselectivity is perhaps because of the a coordination of iridium Ir-N or Ir-O.

Organic Letters published new progress about 89694-44-0. 89694-44-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is 2-Bromo-5-methoxybenzene boronic acid, and the molecular formula is C7H8BBrO3, Synthetic Route of 89694-44-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Garcia-Lopez, Jose-Antonio published the artcileUse of 2-Bromophenylboronic Esters as Benzyne Precursors in the Pd-Catalyzed Synthesis of Triphenylenes, Quality Control of 89694-44-0, the publication is Organic Letters (2014), 16(9), 2338-2341, database is CAplus and MEDLINE.

Ortho-Substituted aryl boronates, e.g., I (X= Br, OTf), are introduced as aryne precursors for transition-metal-catalyzed transformations. On treatment with ^tBuOK and Pd(0), metal-bound aryne intermediates are formed that undergo effective trimerization to form useful triphenylene compds, e.g., II. For meta-substituted arynes, the 3:1 product ratio in favor of non-C₃ sym. material is indicative of a benzyne mechanism.

Organic Letters published new progress about 89694-44-0. 89694-44-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronic Acids,Boronic acid and ester, name is 2-Bromo-5-methoxybenzene boronic acid, and the molecular formula is C7H8BBrO3, Quality Control of 89694-44-0.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Kelso, Robert G. published the artcileThe synthesis and properties of 1,1,2-trimethylcyclopropane, Category: bromides-buliding-blocks, the publication is Journal of the American Chemical Society (1952), 287-92, database is CAplus.

The reaction between Me₂CBrCH₂CHBrMe and Zn in aqueous PrOH at 0° carried out on a large scale permitted a thorough study of the reaction products. 1,1,2-Trimethylcyclopropane (I) comprised 68% of the hydrocarbon mixture obtained in 67% yield. Me₂CHPr, CH₂:CMePr (II), b₇₆₀ 61°, n_D²⁵ 1.3916, and Me₂C:CHEt, b₇₆₀ 64.5-5.5°, n_D²⁵ 1.3987-1.3995, were also obtained; MeCH:CHCHMe₂ was present in minor amount Com. Me₂C(OH)CH₂CH(OH)Me (18 moles) and PBr₃ yielded 4112 g. crude Me₂CBrCH₂CHBrMe (III), b₅ 65-70°, n_D²⁰ 1.496-1.498. (CMe:CH₂)₂, and anhydrous HBr yielded 70% H₂CBrCHMeCBrMe₂, b₁₀ 76°, and 30% (CBrMe)₂, m. 160-4°, b₁₀ 78°. The product of AcII and Me₂CH₂CHO reduced over Raney Ni at 70° and 1500 lb./sq. in. yielded 13% MeCH(OH)CMe₂CH₂OH (IV), b₂₀ 121°, n_D²⁰ 1.4408; IV with PBr₃ at 0° yielded MeCHBrCH₂CBrMe₂. The following constants were determined: for I, f.p., -138.27°, m.p. -138.30°, b₇₆₀ 52.55, dt/dp 0.039, d₄²⁰ 0.6947, n_D²⁰ 1.3864, dn_D/dt 0.00054, n_D²⁵ 1.3834; for CH₂:CMeCHMe₂, b₇₆₀ 55.6°, n_D²⁵ 1.3874; for (Me₂C:)₂, b₇₆₀ 73.3°, n_D²⁵ 1.4070.

Journal of the American Chemical Society published new progress about 594-81-0. 594-81-0 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 2,3-Dibromo-2,3-dimethylbutane, and the molecular formula is C6H12Br2, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Lutter, Ferdinand H. published the artcileCobalt-Catalyzed Cross-Coupling of Functionalized Alkylzinc Reagents with (Hetero)Aryl Halides, Product Details of C7H13BrSi, the publication is Angewandte Chemie, International Edition (2020), 59(14), 5546-5550, database is CAplus and MEDLINE.

A combination of 10% CoCl₂ and 20% 2,2′-bipyridine ligands enables cross-coupling of functionalized primary and secondary alkylzinc reagents RZnY (R = 3-phenylpropyl, 3-(2,5-dimethyl-1H-pyrrol-1-yl)propyl, cyclopropyl, etc.; Y = Cl, Br) with various (hetero)aryl halides R¹X (R¹ = 5-cyanopyridin-2-yl, quinolin-2-yl, pyrimidin-2-yl, etc.; X = Cl, Br). Couplings with 1,3- and 1,4-substituted cycloalkylzinc reagents R²ZnI (R² = 3-methylcyclohexyl, 4-(1H-pyrrol-1-yl)cyclohexyl, (4R,4aS,6R,8aR)-4,4a-dimethyl-6-(propan-2-yl)-decahydronaphthalen-2-yl, etc.) proceeded diastereoselectively leading to functionalized heterocycles R¹R² with high diastereoselectivities of up to 98:2. Furthermore, alkynyl bromides R³CCBr (R³ = Ph, tris(propan-2-yl)silyl) react with primary and secondary alkylzinc reagents RZnY (R = 2-(1,3-dioxan-2-yl)ethyl, 4-phenylcyclohexyl; Y = Cl, I) providing the alkylated alkynes RCCR³.

Angewandte Chemie, International Edition published new progress about 69361-41-7. 69361-41-7 belongs to bromides-buliding-blocks, auxiliary class PROTAC Linker,Aliphatic Linker, name is (4-Bromobut-1-yn-1-yl)trimethylsilane, and the molecular formula is C7H13BrSi, Product Details of C7H13BrSi.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Ji, Jian published the artcileBase-Induced Highly Regioselective Synthesis of N²-Substituted 1,2,3-Triazoles under Mild Conditions in Air, Recommanded Product: 1-Bromododecane, the publication is Organic Letters (2022), 24(1), 132-136, database is CAplus and MEDLINE.

A highly regioselective base-induced synthesis of N²-substituted 1,2,3-triazoles from N-sulfonyl-1,2,3-triazoles and alkyl bromides/alkyl iodides at room temperature is reported. An S_N2-like mechanistic pathway to explain the high N₂-regioselectivity is proposed. The protocol features a broad substrate scope and generates products in good to excellent yields (72-90%).

Organic Letters published new progress about 143-15-7. 143-15-7 belongs to bromides-buliding-blocks, auxiliary class Bromide,Aliphatic hydrocarbon chain, name is 1-Bromododecane, and the molecular formula is C12H25Br, Recommanded Product: 1-Bromododecane.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary